Rapid warming along the Antarctic Peninsula and puzzling shifts in the distribution and extent of winter sea ice at the bottom of the world appear to have their roots in a natural climate swing centered in the tropical Atlantic, according to a new study by researchers at New York University.

The warming of the region is of concern because of its implications for sea-level rise, while the shifting and slight increase in winter sea ice has become a favorite talking-point among many of global warming’s political skeptics.

The climate swing the researchers discussed, known as the Atlantic Multidecadal Oscillation (AMO), shows up as a cycle of warmer, then colder-than-normal sea-surface temperatures. The cycle repeats itself once every 40 to 80 years or so, with cooler or warmer temperatures lasting for periods of 20 to 40 years or more. Since the mid-1990s, the AMO has been in a warm phase.

If the results hold up to additional scrutiny, they would suggest that the initial trigger for the rapid warm-up of the Antarctic Peninsula and a key driver behind its intensification to date is natural variability, in addition to any influence from global warming.

And suddenly we see the anti-AGW crowd adopt actual scientists into their propaganda machine. It would be awkward if they have to explain how the same people they’ve been accusing of fraud and ignoring actual evidence have suddenly changed their positions in light of new evidence… but they won’t.